INFLUENCE OF SOME MAIZE CULTIVARS LINES (ZEA-MAYS L) ON BIOLOGICAL CHARACTERS OF THE AFRICAN ARMYWORM, SPODOPTERA-EXEMPTA (WALKER) (LEPIDOPTERA, NOCTUIDAE)

Five maize cultivars and lines; Michoacan 12, BS 13, Passat, Pool 6 an d OH 43, were evaluated, under laboratory conditions, for the influenc e on a number of biological characters, including mortality, growth an d development, of the African armyworm, Spodoptera exempta L. (Walker) (Lepidoptera: Noctuidae). Overall larval mortality ranged from 36% (P ool 6) to 63% (OH 43). Larvae reared on Michoacan 12 and Pool 6 were s ignificantly heavier than those reared on BS 13. Michoacan 12, Passat and Pool 6 supported significantly shorter larval durations (for mixed sexes) compared with BS 13. Larvae feeding on OH 43 supported longer larval durations than on the other cultivars. Female pupae from larvae reared on OH 43 were significantly lighter compared with those reared on the other cultivars while those from larvae reared on Michoacan 12 were significantly heavier than males. Pupae from any of the five cul tivars showed no significant differences in duration for mixed sexes. However, within Michoacan 12, BS 13 and Pool 6 cultivars, male pupae h ad significantly longer durations than females. Pupal mortality was si gnificantly different among cultivars. Insect growth indices were posi tively correlated with overall larval survival for ail cultivars. Impl ications of the results for the control of S. exempta are discussed.